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MITE

Aceria chondrillae (Acarina: Eriophidae)

DESCRIPTION AND LIFE CYCLE This tiny (0.2±–0.3 mm long), gall- forming mite is yellowish orange and has two pairs of legs. Female mites feed on both vegetative and flower buds; the plant forms green galls composed of many small, deformed leaflets around infestations of several hundred mites. Eventually the galls stop growing, begin to dry, and turn to brown. Mites exit the dying galls and crawl or are windblown to infest new plant tissue and other plants. Flower buds are generally destroyed by the gall formation, reducing and sometimes eliminating seed production. Heavily galled plants display a deformed, stunted growth form; leaves and stems turn yellow and the plant is unable to compete effectively with surrounding vegetation. Generations can be completed in 10 days during the summer and new generations are produced up until plant growth is terminated by lack of moisture or fall frosts.

WEED ATTACKED Rush skeletonweed.

HABITAT Capable of tolerating the variety of habitats in which rush skeletonweed is found.

COLLECTION, SHIPPING, AND HANDLING Collect green galls in the early spring (May) and transfer to the release site immediately. Follow standard shipping and handling procedures for plant material containing biological control agents. Redistribute before fall frosts.

RELEASE Place or tie galls in bundles on the new rush skeletonweed. As the galls dry out, the mites will exit and distribute themselves onto new plant material.

MONITORING Determine presence, density, and movement by looking for galls on leaf and flower buds from April to September.

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REFERENCE Cheney, T.M., G.L. Piper, G.A. Lee, F.W. Barr, D.C. Thill, R.B. Hawkes, R.F. Line, R.R. Old, L.L. Craft, Jr., and E.B. Adams. 1981. Rush skeletonweed: biology and control in the Pacific Northwest. Current Information Series No. 585. University of Idaho, College of Agriculture, Cooperative Extension Service, Agriculture Experiment Station, Moscow, Idaho. 4 p.

Figure 38 Aceria chondrillae galls on rush skeletonweed

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MOTH

Agapeta zoegana L. (Lepidoptera: Cochylidae) DESCRIPTION AND LIFE CYCLE Adults, 1±–2 cm long, have yellow bodies with black stripes. Females have a larger body than do males, with a more rounded abdomen, and males have a pair of clasping pincers at the end of the abdomen. Adults emerge from mid-June to mid-August and mating begins almost immediately. Eggs are laid throughout the 10- to 14-day life span. Larvae hatch 7±–10 days after the eggs are laid and migrate into the root crown. Larvae mine the root tissue just below the outer surface, leaving spiral trails covered by a thin, whitish web. Pupation occurs inside the web near the root crown in early fall, and the insect overwinters in this form. WEEDS ATTACKED Diffuse knapweed and spotted knapweed; shows a preference for spotted knapweed. HABITAT Prefers the mesic, cooler areas of the knapweed range in the Bunchgrass and Ponderosa Pine biogeoclimatic zones. Tolerates cold winter temperatures but requires a long growing season to develop; it therefore does not do well at elevations above 1000 m. Rarely found along roadsides or where knapweed is mowed regularly. COLLECTION, SHIPPING, AND HANDLING Collect adult moths in late afternoon to dusk with vacuum aspirators as they emerge from July to August. Standard shipping and handling precautions for adult insects should be observed. Because of the short lifespan of Agapeta adults, they must be collected and transported within 2±–3 days. RELEASE Follow a standard release technique. Pelochrista medullana larvae may destroy Agapeta larvae when they occur on the same root; avoid releasing the two moths at the same site. Release the moths as soon after collection as possible. MONITORING Presence and density are most effectively determined by the number of larvae per root. Dig and remove entire knapweed plant in early June. Lightly scrape the outer surface of the root to expose the spiral tunnelling and webbing from the crown to the tip of the root.

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REFERENCE Muller, H., D. Schroeder, and A. Gassmann. 1988. Agapeta zoegana (L.) (Lepidoptera: Cochylidae), a suitable prospect for biological control of spotted and diffuse knapweed, Centaurea maculosa Monnet de la Marck and Centaurea diffusa Monnet de la Marck (compositae) in North America. Canadian Entomologist 120: 109±–124.

Figure 39 Agapeta zoegana moth

Figure 40 Agapeta zoegana larva

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BEETLE

Agrilus hyperici (Creutzer) (Coleoptera: Buprestidae)

DESCRIPTION AND LIFE CYCLE Adults, brown with a metallic-purple or greenish sheen, are 4±–5 mm long and elongate in shape. Adults emerge from the root crown in July and feed on terminal leaves. Mating begins immediately and eggs are laid near the base of living stems. Larvae tunnel down the stem and enter the root crown where they feed and develop until late fall. One to several larvae may be present on a single root. Larvae tunnelling reduces plant vigour and can decrease biomass by up to 20%. Larvae overwinter in the root and pupation occurs in mid- to late May.

WEED ATTACKED St. John's wort.

HABITAT These beetles are at the northern limit of their distribution in British Columbia. They need warm, dry habitats, as the larvae are prone to fungal attack at damp sites. They prefer large-stemmed St. John's wort plants to feed, develop, and reproduce on.

COLLECTION, SHIPPING, AND HANDLING Use sweep nets to collect adults in late June through July. The beetles are prone to flight, so quick search and capture must be used. Follow standard shipping and handling procedures for insects.

RELEASE A release of 25±–50 adults by standard procedures is sufficient to establish a new colony.

MONITORING Check presence by one of the following methods: sweeping for adults in July, digging and observing roots for tunnelling scars, or cutting open crowns and root stocks in late fall to look for tunnelling and larvae. Tunnelling scars on the stem base appear as thin, brown lines, lightly scored into the stem surface. Early stages of the larvae are small (<1 mm long) and therefore difficult to see until they enlarge in the early summer.

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REFERENCES Campbell, C.L., J.P. McCaffrey, and H.W. Homan. 1987. Collection and redistribution of biological control agents of St. John's wort. Current Information Series No. 798. University of Idaho, College of Agriculture, Cooperative Extension Service, Agriculture Experiment Station, Moscow, Idaho. 4 p. Harris, P. and D. Peschken. 1969. The status of biological control of the weed Hypericum perforatum in British Columbia. Canadian Entomologist 101:1±–15.

Figure 41 Agrilus hyperici larva

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APHID

Aphis chloris (Koch) (Hemiptera: Aphididae)

DESCRIPTION AND LIFE CYCLE Several forms of the 1±–2 mm long aphid may be produced during an annual cycle depending on environmental conditions. Generally, cooler temperatures and shorter day lengths stimulate the production of males and egg-producing females in the fall. Eggs, yellow, turning shiny black with age, are laid on the base of flowering stems; the eggs require a cold period in the winter and then continue development the following spring. Eggs hatch in April or May, giving rise to wingless females. Under continued warm conditions, the self-reproducing females develop year round. Both the adults and larvae suck plant fluids from the plant root crown and stem. During the mid-summer, under crowded conditions, winged, fertile females develop and disperse to form new colonies.

WEED ATTACKED St. John's wort.

HABITAT This aphid is found over a wide geographic and climatic range in its native Europe, and is considered to be contiguous with St. John's Wort distribution in British Columbia.

COLLECTION, SHIPPING, AND HANDLING Collect whole plants infested with egg-producing females in mid-summer and transport in nursery containers. Ship to the release site as soon as possible, as the aphids require living plant material to feed on.

RELEASE Transplant the infested nursery plants into an infestation of St. John's wort. The aphids will disperse themselves onto adjacent plants to form new colonies.

MONITORING Aphid's presence can be observed on plant material throughout the summer months.

REFERENCES Briese, D.T. 1988. Bionomics of Aphis chloris Koch (Hemiptera: Aphididae) for biological control of St. John's wort in Australia. Ecological Entomology 13:365±–374.

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Harris, P. and M. Maw. 1984. Hypericum perforatum L., St. John's wort (Hypericaceae). In J.S. Kelleher and M.A. Hulme (editors). Biological control programmes against insects and weeds in Canada 1969–±1980. Commonwealth Agricultural Bureaux, Farnham, England. pp. 171±–177.

Figure 42 Aphis chloris

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BEETLE

Aphthona cyparissiae (Koch) (Coleoptera: Chyrsomelidae) DESCRIPTION AND LIFE CYCLE Bronze-coloured adults, oval-shaped and 2±–3 mm long, emerge in late June or early July and feed near the top of the shoot and at the leaf edges. The small triangle at the top of the wing cover (the scutellum) is brown, and thus the beetle can be distinguished from the similar Aphthona nigriscutis, which have black scutella. The beetles mate and egg laying occurs below the soil surface near the roots. Egg laying can continue until freeze-up. Eggs hatch in 2±–3 weeks and the larvae burrow into the roots. Larvae build an overwinter cell in the soil and require a 4 month cold period to initiate further development. They resume root feeding in the spring and then pupate in the soil. WEEDS ATTACKED Leafy spurge. HABITAT Prefer open sites, hot summer temperatures, and moist sandy- loam soils where the height of flowering spurge is 60 cm or taller and no bare ground is visible. They appear to do best on the bottom section of valley slopes and in slightly depressed areas. They do not do well on northern aspects, in partial shade, in dry areas with partially bare ground, or on clay soils with organic matter content greater than 4%. COLLECTION, SHIPPING, AND HANDLING Collect adults in late June to early July with a sweep net. Follow standard shipping and handling requirements for insects. RELEASE A release of 200 adults is sufficient to establish a new colony. Adults prefer to be in a dense population, so do not scatter insects at the release point; deposit all the insects of a given release in a single spot. MONITORING Adult presence can be determined with sweep nets in July. During the first few years, adults should be located within a few metres of the release point because their initial spread is slow. They will, however, fly readily and distribute themselves when spurge becomes depleted. If presence is detected 1 year after release, it almost always indicates establishment. In approximately half the cases in

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which none were detected by sweeping 1 year after release, the beetles were present in subsequent years. REFERENCE Sommer, G. and E. Maw. 1982. Aphthona cyparissiae (Koch) and A. flava (Fahr.) (Coleoptera: Chrysomelidae): two candidates for the biological control of cypress and leafy spurge in North America. European Station Report, C.A.B. International Institute of Biological Control, Delemont, Switzerland. 42 p.

Figure 43 Aphthona cyparissiae

Figure 44 Aphthona cyparissiae larva

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BEETLE

Aphthona czwalinae Weise (Coleoptera: Chrysomelidae)

DESCRIPTION AND LIFE CYCLE Black adults, 2.9±–3.1 mm long, emerge throughout the spring, with high mortality among the early emergences. The main emergence occurs from June through to July. Adults have a relatively brief life span of 2±–4 weeks, and mating begins immediately with egg laying within 1±–2 weeks after emergence. Adults feed on leaf tissue and new shoots; small, young leaves can be completely consumed. Females normally lay the oval-shaped, yellowish eggs into crevices and holes in the soil surface, where the ovipositor does not come into contact with the soil. Eggs mature over a 16 day period and newly emerged larvae transfer to leafy spurge roots. Larvae are not readily distinguished from other Aphthona species; they show the typical elongated, whitish body with light brown head. Larvae feed on root tissue and develop over a period of at least 88 days. After the feeding period, larvae re-enter the soil and construct cells in which they hibernate. A 4 month cold period (<4°C) is required to initiate pupation and further development in the hibernation cell.

WEED ATTACKED Leafy spurge.

HABITAT This flea-beetle is most frequently associated with mesic moisture regimes and loam-textured soils, where the host plants are intermixed with other vegetation. The beetle is not generally found in open, dry sites.

COLLECTION, SHIPPING, AND HANDLING Collect adults with sweep nets in June or July. Follow standard shipping and handling requirements for insects.

RELEASE Follow standard release requirements for insects; a release of 200 adults is sufficient to establish a new colony.

MONITORING Adult presence can be determined with sweep nets in June or July. During the first few years, adults should be located within a few metres of the release point. A large area may have to be searched because these flea-beetles maintain very low densities.

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REFERENCE Gassmann, A. 1984. Aphthona czwalinae Weise (Coleoptera: Chrysomelidae): A candidate for the biological control of leafy spurge in North America. European Station Report, Commonwealth Institute of Biological Control, Delemont, Switzerland. 17 p.

Figure 45 Aphthona czwalinae adult

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BEETLE

Aphthona ¯falavvaa Guill. (Coleoptera: Chrysomelidae)

DESCRIPTION AND LIFE CYCLE Orange-brown adults, 2±–3 mm long, emerge in July and feed near the top of shoots and at the leaf edges. The flea-beetles mate, and females lay eggs below the soil surface near a root. Egg laying can continue until freeze-up. Eggs hatch in 2±–3 weeks and the larvae burrow into the roots. Larvae build an overwinter cell in the soil and require a 4 month cold period to initiate further development. They resume root feeding in the spring and then pupate in the soil.

WEEDS ATTACKED Leafy spurge.

HABITAT Exact habitat preferences have not been determined. Preliminary information suggests that they prefer sites that have hot summer temperatures, are lightly shaded, and possess moister soil conditions than are associated with other Aphthona species. River benches and lake shores, or other areas with high water tables in valley bottoms, may be suitable. The beetle has been associated with cottonwoods (Populus spp.) and fairly widely spaced spurge plants.

COLLECTION, SHIPPING, AND HANDLING Collect adults with sweep nets in late July. Follow standard shipping and handling procedures for adult insects.

RELEASE Follow standard release procedures for insects; a release of 200 adults is sufficient to establish a new colony.

MONITORING Adult presence can be determined with sweep nets in July. During the first few years, adults should be located within a few metres of the release point.

REFERENCE Sommer, G. and E. Maw. 1982. Aphthona cyparissiae (Koch) and A. flava (Fahr.) (Coleoptera: Chrysomelidae): two candidates for the biological control of cypress and leafy spurge in North America. European Station Report, C.A.B. International Institute of Biological Control, Delemont, Switzerland. 42 p.

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Figure 46 Aphthona flava

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BEETLE

Aphthona lacertosa Rosh. (Coleoptera: Chrysomelidae) DESCRIPTION AND LIFE CYCLE Black adults, 3 mm long, can be distinguished from the similar A. czwalinae by the light to dark brown, rather than black, femur on the hind legs. Mating and egg laying begin soon after emergence in June and July. Females deposit their eggs in batches in the soil near a host plant; egg laying continues over a 2 month period while the adults feed on shoot and lower leaves. The developing larvae feed on root tissue, and leave the plant to form pupal cells in the soil in late fall. A 4 month cold period is required to initiate pupal development in the overwinter hibernation cells. WEED ATTACKED Leafy spurge. HABITAT This beetle has a wide adaptation to climatic conditions; it is generally more adapted to mesic-dry to moist conditions than are other Aphthona species. It is highly intolerant of spring flooding. It generally prefers loam to clay loam-textured soils and the host plant should be surrounded by a well-developed herbaceous community. COLLECTION, SHIPPING, AND HANDLING Collect adults with sweep nets in June or July. Follow standard shipping and handling requirements for insects. The parasitic protozoan, Nosema sp., can cause high mortality in the larval populations: do not collect and redistribute adults from areas where this parasite is known to occur. RELEASE Follow standard release requirements for insects; a release of 200 adults is sufficient to establish a new colony. MONITORING Adult presence can be determined with sweep nets in June or July. During the first few years, adults should be located within a few metres of the release point.

REFERENCE Gassmann, A. 1990. Aphthona lacertosa (Rosh.) (Coleoptera: Chrysomelidae): a candidate for the biological control of leafy spurge and cypress spurge in North America. European Station Report. International Institute of Biological Control, Delemont, Switzerland. 22 p.

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Figure 47 Aphthona lacertosa

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BEETLE

Aphthona nigriscutis Foudras (Coleoptera: Chrysomelidae) DESCRIPTION AND LIFE CYCLE Adults, 2±–3 mm long, oval shaped, and bronze coloured with a black dot at the tip of the wing cover (scutellum), emerge in late June or early July and feed near the top of the shoot and at the leaf tips. The beetles mate and egg laying occurs below the soil surface near a root. Eggs hatch in 2±–3 weeks and the larvae burrow into the roots. Larvae build an overwinter cell in the soil and require a 4 month cold period to initiate further development. They resume root feeding in the spring and then pupate in the soil. In some releases, combined adult and larval feeding have reduced spurge vegetative cover by 95%. WEEDS ATTACKED Leafy spurge. HABITAT These beetles prefer open-canopied sites with hot, dry summer conditions. They appear to do best on coarse-textured, open soils with low organic matter content (<3%), particularly on southern slopes or knolls. They do not do well in shaded areas or in moist depressions. They prefer vegetation in which the height of spurge in flower does not exceed 50 cm, accompanied by bunchgrasses and some bare ground. COLLECTION, SHIPPING, AND HANDLING Collect adults with sweep nets in mid-June to early-July. Follow standard shipping and handling procedures for insects. RELEASE A release of 200 adults is sufficient to establish a new colony. Adults prefer to be in a dense population, so do not scatter insects at the release point. Instead, deposit all the insects of a given release in a single spot. MONITORING Adult presence can be determined with sweep nets in July. During the first few years, adults should be located within a few metres of the release point because their initial spread is slow. They will, however, fly readily and distribute themselves when spurge becomes depleted. If presence is detected 1 year after release, it almost always indicates establishment. In approximately half the cases in

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which none was detected by sweeping 1 year after release, the beetles were present in subsequent years.

REFERENCE Gassmann, A. 1985. Aphthona nigriscutis Foudras (Coleoptera: Chrysomelidae): a candidate for the biological control of cypress and leafy spurge in North America. European Station Report, C.A.B. International Institute of Biological Control, Delemont, Switerland. 19 p.

Figure 48 Aphthona nigriscutis

Figure 49 Aphthona nigriscutis larva

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MOTH

Aplocera plagiata L. (Lepidoptera: Geometridae)

DESCRIPTION AND LIFE CYCLE These mottled-brown moths can produce two generations each year. Insects overwinter as larvae and begin feeding early in the spring (March to April); the caterpillar-style larvae defoliate plants. Pupation occurs in late spring and first- generation adults emerge in early summer. The mating and egg laying begin soon after emergence; eggs develop on the plant and newly emerged larvae feed on foliage.

WEED ATTACKED St. John's wort.

HABITAT Prefers dry, rocky habitats, open sandy places, and limestone regions. These moths are adapted to withstand both high and low temperature extremes. They are widely distributed in the East and West Kootenay areas.

COLLECTION, SHIPPING, AND HANDLING Adults are readily swept or aspirated from dead flower stalks in October. Follow standard shipping and handling for insects.

RELEASE Follow standard release procedures for insects.

MONITORING Determine presence by observing larvae or adults from spring through fall.

REFERENCE Harris, P. and D. Peschken. 1969. The status of biological control of the weed Hypericum perforatum in British Columbia. Canadian Entomologist 101:1±–15.

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Figure 50 Aplocera plagiata moth

Figure 51 Aplocera plagiata caterpillar

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BEETLE

Brachypterolus pulicarius L. (Coleoptera: Nitidulidae)

DESCRIPTION AND LIFE CYCLE Black adults, 1±–2 mm long and elongate to oval in shape, emerge in May and feed on young stems. Mating occurs in June and females lay eggs into the flower buds. Larvae feed on reproductive organs in the flowers; older larvae will also feed on seeds. Larval feeding can reduce seed production by three- quarters or more. Larvae migrate into the soil in late summer to begin pupation, though some may remain in the flowers as larvae until freezing temperatures occur in late fall.

WEEDS ATTACKED Yellow toadflax and Dalmatian toadflax.

HABITAT These beetles are capable of inhabiting all areas where yellow toadflax or Dalmatian toadflax occur.

COLLECTION, SHIPPING, AND HANDLING Collect adults with sweep nets or by vacuum aspiration in early summer. Follow standard shipping and handling procedures for insects.

RELEASE Follow standard release procedures for insects.

MONITORING Monitor for presence in late spring to early summer using sweep nets. Open flowers and seedheads to look for larvae in late summer and fall.

REFERENCE McClay, A.S. 1992. Effects of Brachypterolus pulicarius L. (Coleoptera: Nitidulidae) on flowering and seed production of common toadflax. Canadian Entomologist 124:631±–636.

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Figure 52 Brachypterolus pulicarius

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MOTH

Calophasia lunula (Hufn.) (Lepidoptera: Noctuidae)

DESCRIPTION AND LIFE CYCLE Adults are pale to dark brown with a white crescent marking and other white markings on the central portion of the wing. Adults are 12±–14 mm long with a 27–±30 mm wingspan. Adults emerge from May to August and live for 3–±12 days. Mating begins immediately and egg laying starts after 1±–2 days. Larvae, pearl-coloured with five yellow stripes along the back and sides, hatch in 7±–11 days and begin feeding on leaves. Pupation occurs in the summer and continues until fall. Those that pupate in the beginning of summer can produce second-generation adults by late summer or early fall. A third generation is possible, though most larvae pupate and overwinter as second-generation pupae.

WEEDS ATTACKED Yellow toadflax and Dalmatian toadflax.

HABITAT Areas with warm summer temperatures are needed to complete larval development.

COLLECTION, SHIPPING, AND HANDLING Hand pick larvae from plants from mid-summer to fall. Moths can be collected using a vacuum aspirator or sweep net from May to August, although they are very fragile and susceptible to damage. Best collection times are late afternoon and dusk. Follow standard shipping and handling procedures for insects. Because of the short lifespan of adults, they must be collected and shipped within 1 or 2 days. If this is not feasible, larvae must be collected and redistributed.

RELEASE Follow standard release procedures for insects. Release as soon after collection as possible.

MONITORING Determine presence by observing larvae feeding on the plants in summer or by collecting adults with sweep nets from May to August.

REFERENCE Karny, M. 1963. The possibilities of Calophasia lunula Hufn. (Lep.: Noctuidae) in the biological control of toadflax, Linaria vulgaris

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Mill. Technical Bulletin No. 3. C.A.B. Commonwealth Institute of Biological Control, Delemont, Switzerland, pp. 1–±26.

Figure 53 Calophasia lunula moth

Figure 54 Calophasia lunula caterpillar

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BEETLE

Ceutorhynchus litura (F.) (Coleoptera: Curculionidae) DESCRIPTION AND LIFE CYCLE Adults, 2±–3 mm long, are mottled- grey with a white-cross marking on the back. Overwintered adults begin to emerge from hibernation coinciding with the rosette stage of Canada thistle. Females feed on leaf tissue and lay eggs into the mid- vein of rosette leaves. Within a few days the larvae enter and mine the main stems, and then move down to the root collar, leaving long black tunnels in the stem. In areas where the springs are long and cool, with protracted vegetative growth, the larvae will tunnel and feed in the root crown. They can achieve 90% or greater control. In areas where the spring is short and growth is rapid, larval feeding is confined to the stem and little damage is done to the thistle. Mature larvae burrow out of the plant and pupate in the soil. Adults emerge from late June into the early part of July; they feed on foliage and hibernate in leaf litter over the winter. WEED ATTACKED Canada thistle. HABITAT Prefers dense stands of thistle (5±–10 plants per square metre) with bare soil surrounding the thistles rather than thick grass. Adults can withstand some spring flooding. COLLECTION, SHIPPING, AND HANDLING Collect by sweeping green thistle plants on calm, warm, sunny days in August. Sweep vertically from the bottom of the plant upwards and put debris in a bucket. Weevils will feign death, but can be easily sorted when they begin moving. Vacuum aspirators can be employed on small bolting plants and rosettes. Follow standard shipping and handling requirements for insects. RELEASE Follow standard release procedures for insects. MONITORING Monitor establishment by cutting open stems on the largest Canada thistle plants to check for stem mining and larvae at the root crown in the first year. In the second and subsequent years after release, as weevil population density increases, check for larvae mining below the root crown.

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REFERENCES Peschken, D.P. and J.L. Derby. 1992. Effect of Urophora cardui (L.) (Diptera: Tephritidae) and Ceutorhynchus litura (F.) (Coleoptera: Curculionidae) on the weed Canada thistle, Cirsium arvense (L.) Scop. Canadian Entomologist 124:145±–150. Rees, N. 1990. Establishment, dispersal, and influence of Ceutorhynchus litura on Canada thistle (Cirsium arvense) in the Gallatin Valley of Montana. Weed Science 38:198–±200.

Figure 55 Ceutorhynchus litura

Figure 56 Ceutorhynchus litura larva

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FLY

Chaetorellia acrolophi White & Marq. (Diptera: Tephritidae) DESCRIPTION AND LIFE CYCLE Adults, dark bodied with yellow bands on body and wings, emerge in early June coinciding with the budding of spotted knapweed. Mating begins immediately and females lay eggs into flower buds throughout their 17 day life span. Larvae emerge 4±–5 days after eggs are laid, and migrate into the centre of the flower buds. Pupation occurs 5±–15 days after larvae hatch. Chaetorellia generally produce two generations per year, with a generation overlap in July. First-generation larvae and pupae are white and pupae are enclosed in a white pupal case covered with pappus hairs from the seeds; pupae emerge as adults in July, mate, and produce a second generation. Second-generation larvae and pupae are yellow, with pupae enclosed in a yellow pupal case covered with pappus hairs from the seeds. A third generation is possible, but rare. Second-generation larvae typically overwinter in the flower heads, consuming florets and seeds, and pupate in the spring. WEED ATTACKED Spotted knapweed. HABITAT Prefers south-facing slopes, and dry habitats. Generally associated with scattered plants, rather than dense stands of spotted knapweed. COLLECTION, SHIPPING, AND HANDLING Collect by removing spotted knapweed seedheads containing larvae or pupae, and redistribute plants. Follow standard shipping and handling requirements for plant material containing biological control agents. RELEASE Follow standard release procedure for biological control agents in plant material. MONITORING Determine presence by breaking open spotted knapweed seedheads to look for larvae or pupae, from late summer through to the next spring. Chaetorellia larvae can be distinguished from Urophora by the colour of the pupal case: Urophora have brown pupal cases; Chaetorellia are white or yellow depending on the generation.

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REFERENCE Grippe, K. and K. Marquardt. 1989. Chaetorellia acrolophi White & Marquardt (Diptera: Tephritidae), a suitable candidate for the biological control of diffuse and spotted knapweed in North America. European Station Report. C.A.B. International Institute of Biological Control, Delemont, Switzerland. 29 p.

Figure 57 Chaetorellia acrolophi larvae in knapweed seedhead

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BEETLE

Chrysolina hyperici (Forster) (Coleoptera: Chrysomelidae)

DESCRIPTION AND LIFE CYCLE Adults are metallic bronze-green coloured, 4–±5 mm long, and emerge in early June. They feed on flower buds and terminal leaves until leaf drop in late July to early August. After leaf drop, adults aestivate in leaf litter until fall moisture reactivates them for mating; they require considerable moisture to break this dormant period. Mating occurs in the autumn, and females lay orange-coloured eggs on the basal foliage. Most overwinter as eggs, and larvae hatch in the spring, though some hatch in the fall, and have good winter survival (approximately 20%). Overwintering adults lay large numbers of eggs in the following spring. Larvae feed nocturnally on shoot tips and the basal and developing leaves. These beetles can be highly effective in controlling St. John's wort, and have reduced dense stands of several square kilometres to scattered plants. Larvae are fully developed by about mid-May, when they leave the plant to pupate in the soil. Chrysolina beetles can be distinguished from each other by the relative size of the beetle: C. hyperici are approximately two-thirds the size of C. quadrigemina.

WEED ATTACKED St. John's wort.

HABITAT Compared to C. quadrigemina these beetles are generally more tolerant of cooler, moist to wet summers, and areas with cold winters lacking continuous snow cover. They do not do well in shaded forest conditions.

COLLECTION, SHIPPING, AND HANDLING Adults will cluster along the ends of the stems; sweep in early to mid-June during the initial bloom of St. John's wort, or tap stems over a collection tray or funnel. Follow standard shipping and handling for adult insects.

RELEASE Releases of 200±–1000 adults are sufficient to establish new colonies. Use standard release procedures for insects.

MONITORING Visual checks of upper stem for adult beetle clustering in June and July are adequate for determining presence.

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REFERENCE Campbell, C.L., J.P. McCaffrey, and H.W. Homan. 1987. Collection and redistribution of biological control agents of St. Johns wort. Current Information Series No. 798. University of Idaho, College of Agriculture, Cooperative Extension Service, Agriculture Experiment Station, Moscow, Idaho. 4 p.

Figure 58 Chrysolina hyperici and Chrysolina quadrigemina beetles

Figure 59 Chrysolina spp. larva 84 forestryweeds7.qxd 11/14/99 7:42 PM Page 97

BEETLE

Chrysolina quadrigemina (Suffrain) (Coleoptera: Chrysomelidae) DESCRIPTION AND LIFE CYCLE Metallic bronze-, blue-, green-, or purple-coloured adults, 7 mm long, emerge in early June to coincide with flower bud development on St. John's wort. Adults feed on flower buds and terminal leaves until leaf drop in late July to early August. After leaf drop, adults aestivate in leaf litter until fall moisture reactivates them for mating. Mating occurs in the autumn, and females lay many orange-coloured eggs on the basal foliage. Most overwinter as eggs and larvae hatch in the spring, though some hatch in the fall, surviving if the winter is moderate. Larvae feed nocturnally on shoot tips, and on the basal and developing leaves. These beetles can be highly effective in controlling St. John's wort, and have reduced dense stands of several square kilometres to scattered plants. Larvae are fully developed by about mid-May, when they leave the plant to pupate in the soil. May frosts of −10°C without snow cover kill all surviving larvae and adults. Chrysolina beetles can be distinguished from each other by the relative size of the beetle; C. hyperici are approximately two-thirds the size of C. quadrigemina. Refer to C. hyperici photos for identification. WEED ATTACKED St. John's wort. HABITAT These beetles are generally more abundant in Mediterranean type climates. They do not do well in shaded forest conditions or areas with heavy summer rainfall, either of which prematurely break the summer dormancy. COLLECTION, SHIPPING, AND HANDLING Adults will cluster along the ends of the stems; sweep in early to mid-June during the initial bloom of St. John's wort, or tap stems over a collection tray or funnel. Because males emerge before females, allow at least 1 week from the first emergence to ensure mixture of males and females. Follow standard shipping and handling for adult insects. RELEASE Releases of 200±–1000 adults are sufficient to establish new colonies. Use standard release procedures for insects.

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MONITORING Visual checks of upper stem for adult beetle clustering in June and July are adequate for determining presence.

REFERENCE Campbell, C.L., J.P. McCaffrey, and H.W. Homan. 1987. Collection and redistribution of biological control agents of St. Johnswort. Current Information Series No. 798. University of Idaho, College of Agriculture, Cooperative Extension Service, Agriculture Experiment Station, Moscow, Idaho. 4 p.

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MOTH

Cochylis atricapitana (Stephens) (Lepidoptera: Cochylidae)

DESCRIPTION AND LIFE CYCLE Adults are tan-coloured, with a dark, saddle-shaped mark across the upper surface of the wings. They are small (3 mm long), with a wingspan of 7 mm, very fragile, and active only at night. Cochylis are capable of multiple generations per year; it typically takes 33 days to complete a generation in the summer. Eggs are laid on the surface of the root crown where the white larvae hatch and mine into the crown tissue. Larvae feed on the upper root crown and rarely on the roots. Pupation occurs in the root; pupae change colour from white to tan as they develop.

WEED ATTACKED Tansy ragwort.

HABITAT These moths are adapted to all the habitats supporting tansy ragwort, though they are more effective in controlling the weed at higher elevations.

COLLECTION, SHIPPING, AND HANDLING Adults are too fragile and prone to damage for collection and redistribution. Collect larvae- infested roots throughout the summer. Transplant infested roots into nursery containers and keep the soil moist, but not saturated, during shipping and handling.

RELEASE Place the nursery containers directly at the release site and allow adults to emerge. Maintain moist conditions in the nursery containers during the emergence period. If livestock disturbance is possible, fence off the release area temporarily. A release of 50±–100 larvae is sufficient to establish a new colony.

MONITORING Determine presence and density of larvae by observing the centre of the rosette root crown. Adults stay very close to the ground during the day, with little activity. Adult presence may sometimes be detected with the use of a sweep net brushed close to the ground.

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Figure 60 Cochylis atricapitana moth

Figure 61 Cochylis atricapitana larval damage on tansy ragwort

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BEETLE

Cyphocleonus achates (Fahr.) (Coleoptera: Curculionidae) DESCRIPTION AND LIFE CYCLE Mottled grey-brown adults, 50±175– mm long, emerge in mid-July to early September and begin mating within 1±2– weeks with the early-emerged adults and immediately with later emergences. Females lay eggs in the root crown over their 10 week life span. Larvae hatch 10±12– days after eggs are laid and tunnel and feed in the root overwinter. Pupation occurs in the following spring. WEEDS ATTACKED Diffuse knapweed and spotted knapweed; shows a preference for spotted knapweed. HABITAT Prefer hot, dry conditions on well-drained, coarse-textured and sandy soils. COLLECTION, SHIPPING, AND HANDLING Collect adults by hand picking from the plants. Weather conditions will determine location of the weevil. During hot weather, weevils will locate on the upper portions of the stems. During cool and wet weather, the weevils will bury themselves in the leaf litter and loose soil around the base of the plant. If disturbed, weevils may feign death and drop to the ground. Their mottled colour may camouflage them in the leaf litter. Follow standard shipping and handling procedures for insects. RELEASE Follow standard release procedures for insects. Dense stands are generally required for release because the weevils do not fly, but distribute themselves by walking. MONITORING Determine presence by locating adults or larvae. Adults can be observed on warm days on the upper stem, from June to August. Plants that have been attacked tend to bolt over two consecutive years. Dig up the entire root and cut it open, examining the central portion of root. Tunnelling damage in the later stages of larval development is extensive and easy to identify.

REFERENCE Stinson, C.S.A. 1987. Investigations on Cyphocleonus achates (Fahr.) (Col.: Curculionidae), a possible biological agent of spotted

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knapweed (Centaurea maculosa Lam.) and diffuse knapweed (C. diffusa Lam.) (Compositae) in North America. European Station Report. C.A.B. International Institute of Biological Control, Delemont, Switzerland. 37 p.

Figure 62 Cyphocleonus achates

Figure 63 Cyphocleonus achates larva

Figure 64 Naked pupa of Cyphocleonus achates

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MOTH

Eteobalea intermediella Riedl (Lepidoptera: Cosmopterigidae)

DESCRIPTION AND LIFE CYCLE Black adults have yellow heads, metallic-gold flecks on the black wings, and a wingspan of 16±–18 mm. E. intermediella and E. serratella can only be positively distinguished from one another by the male's genitalia (E. serratella being distinct), or the egg structure. Adults emerge in late spring and live approximately 2 weeks. Mating begins immediately and egg laying occurs on the leaf axils or stem base. Larvae hatch 9±–10 days after egg laying; larvae bore into the stem and feed on small roots and the root crown. E. intermediella has two generations per year, with second- generation adults emerging in late fall. The second-generation larvae overwinter in the root and pupate in the following spring. Pupae are light brown, turning to black with age.

WEED ATTACKED Dalmatian toadflax.

HABITAT No information on habitat preference is currently available.

COLLECTION, SHIPPING, AND HANDLING Collect adults with aspirators or sweep nets; peak adult activity is 1±–2 hours before sunrise and after sunset. Follow standard shipping and handling procedures for insects.

RELEASE Follow standard release procedure for insects.

MONITORING Monitor for adult presence in late spring at dusk or pre- dawn. Monitor larvae or pupae by digging roots and scraping the outer surface near the crown to reveal feeding tunnels.

REFERENCE Saner, M., K. Groppe, and P. Harris. 1990. Eteobalea intermediella Riedl and E. serratella Treitschke (Lep., Cosmopterigidae), two suitable agents for the biological control of yellow and Dalmatian toadflax in North America. European Station Report. C.A.B. International Institute of Biological Control, Delemont, Switzerland. 39 p.

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Figure 65 Eteobalea intermediella moth

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MOTH

Eteobalea serratella Treit. (Lepidoptera: Cosmopterigidae)

DESCRIPTION AND LIFE CYCLE Adults are black, with a yellow head and metallic flecks on the black wings; they have a 16±–18 mm wingspan. E. intermediella and E. serratella can only be positively distinguished from one another by the male's genitalia (E. serratella being distinct), or the egg structure. Adults emerge in early summer and live for 9±–17 days. Mating and egg laying at the stem base begins immediately after emergence. Larvae hatch 15±–20 days after egg laying and mine into the root. Feeding occurs mainly in the root crown area of the plant. Larvae pupate in the fall and overwinter in this form.

WEED ATTACKED Yellow toadflax.

HABITAT No information on habitat preference in British Columbia is currently available. They prefer hot, dry sites in their native Europe.

COLLECTION, SHIPPING, AND HANDLING Collect adults with aspirators or sweep nets. Peak adult activity is 1–±2 hours before sunrise and after sunset. Larvae can be collected by removing plants containing larvae. Follow standard shipping and handling procedures for insects.

RELEASE Follow standard release procedure for insects.

MONITORING Monitor for adult presence in late spring to attract moths at dusk or pre-dawn. Monitor larvae or pupae by digging roots and scraping the outer surface near the crown to reveal feeding tunnels.

REFERENCE Saner, M., K. Groppe, and P. Harris. 1990. Eteobalea intermediella Riedl and E. serratella Treitschke (Lep., Cosmopterigidae), two suitable agents for the biological control of yellow and Dalmatian toadflax in North America. European Station Report. C.A.B. International Institute of Biological Control, Delemont, Switzerland. 39 p.

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Figure 66 Eteobalea serratella moth

Figure 67 Eteobalea serratella larva

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BEETLE

Galerucella calmariensis Linne (Coleoptera: Chrysomelidae)

DESCRIPTION AND LIFE CYCLE Adults, red with black markings, 2–4mmlong,emergefromhibernationandfeedonshoottipsand young leaves in April. Mating begins immediately with egg laying starting approximately 1 week later and continuing until the end of July. Larvae hatch 12 days after egg laying; larvae develop over a 2 week period, feeding initially on leaf and flower buds and then on all parts of the plant in the later stages of development. Mature larvae leave the plant and pupate in leaf litter and the upper portion of the soil. Adults emerge 9±11– days later. Adults emerging before August mate and lay eggs for a 1 month period. Adults feed on foliage and hibernate in the soil before winter.

WEED ATTACKED Purple loosestrife.

HABITAT Tolerates the variety of habitat conditions in which purple loosestrife is found.

COLLECTION, SHIPPING, AND HANDLING Collect with the sweep net technique and use standard shipping and handling procedures.

RELEASE Follow standard release procedures for insects. Take precautions not to dump the beetles in the water.

MONITORING Determine presence by looking for adults on foliage in April or August.

REFERENCE Blossey, B. and D. Schroeder. 1991. Study of potential biological control agents of purple loosestrife (Lythrum salicaria L.). Final Report. European Station Report. C.A.B. International Institute of Biological Control, Delemont, Switzerland. 27 p.

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Figure 68 Galerucella calmariensis

Figure 69 Galerucella calmariensis larvae

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